Family says Scott was killed without provocation; police say he threatened them with a gun.

At least 12 police officers were injured when a North Carolina protest over America's latest police shooting of a black man turned violent on Tuesday (20 September). One officer was hit in the face with a rock, according to police.

The injuries – none of them life-threatening – were reported in a tweet by the Charlotte-Mecklenburg Police Department, but no other details were immediately provided.

Protesters initially surrounded officers who were working at the scene of the fatal police shooting of Keith Lamont Scott at an apartment complex earlier that day.

Witnesses said protesters then began to smash windows and attempted to overturn police vehicles parked at the scene.

"Demonstrators surrounded our officers who were attempting to leave scene" and the Civil Emergency Unit was dispatched "to safely remove our officers," the police department said on Twitter.

Riot police were called out and police helicopters patrolled overhead as the crowd grew to more than 200 demonstrators, NBC reported. Protesters were yelling "Black lives matter," and "Hands up, don't shoot!" One person held aloft a sign saying: "Stop Killing Us."

Officers in riot gear block a road during protests after police fatally shot Keith Lamont Scott in the parking lot of an apartment complex in Charlotte, North Carolina.Reuters/Stringer

Charlotte Mayor Jennifer Roberts appealed to protesters for "calm" while promising a full investigation into the shooting.

Keith Lamont Scott's daughter said he was unarmed and shot without provocation by police. He was reading a book in his car when he was ordered to step out by police, and was tasered and shot four times, she said.

"My Daddy didn't do nothing," she said on a video widely shared on social media. "They just pulled up undercover."

Officials say police seeking a wanted man at a Charlotte apartment complex spotted Scott exit a vehicle "armed with a firearm and posed an imminent deadly threat to the officers who subsequently fired their weapon striking the subject." They said a gun was recovered at the scene.

Protesters take to the street after black man Keith Lamont Scott is killed by US policeStoryful

There has been a spate of shootings by US police in recent days. A 13-year-old boy holding a BB gun was shot dead by police in Columbus, Ohio, on 15 September.

A deeply disturbing video of police-shooting victim Terence Crutcher, 40, shows him holding his hands in the air when he's shot dead during a traffic stop in Tulsa, Oklahoma.

"I'm going to tell you right now, there was no gun on the suspect or in the suspect's vehicle," Tulsa Police Chief Chuck Jordan said about the 16 September shooting. "I want to assure our community and I want to assure all of you and people across the nation: We will achieve justice."